Shovel construction



June 12, 1956 R. RUNKLE SHOVEL CONSTRUCTION 2 Sheets-Sheet 1 Filed March28, 1952 INVEN TOR. Zoe/N E, Paw/ 25 June 12, 1956 RUNKLE SHOVELCONSTRUCTION 2 Sheets-Sheet 2 Filed March 28, 1952 INVENTOR. Zoe/N 2Eu/vzz 6'.

BY may W- United States Patent SHOVEL CONSTRUCTION Application March 28,1952, Serial No. 279,033

4 Claims. (Cl. 294-49) This invention relates to improvements inshovels, and particularly to improvements in utility shovels or spades.

Heretofore it has been the practice in the manufacture of blades ofutility shovels or spades to forge such blades from a thick blank. Theforging operation is time-consuming and therefore costly. Forged shovelblades possess various properties which heretofore have been considerednecessary to a successful practical utility shovel. One of theadvantages is that the blade has varying thickness throughout so thatstrength may be provided in the blade where needed by the simpleexpedient of increasing the thickness of the blade at the pointsrequiring strength. Similarly, the ability to vary the thickness of theblade has been relied upon heretofore to assist in maintaining the shapeof the blade so that it will not become deformed in use. Forged shovelblades also commonly include comparatively thick rear edge portions toprovide surfaces engageable by the users foot when pressing the bladeinto the soil or other dense material in digging, thereby preventing acutting action of the blade upon the shoe of the user.

- The primary object of this invention is to provide a shovel bladewhich is constructed from metal plate or sheet steel of uniformthickness to provide requisite strength and durability, to secure theadvantages. of low cost and light weight, and to serve and possessvarious advantages which heretofore have been considered peculiar to aforged shovel blade.

A further object is to provide a shovel blade formed from two pieces ofsheet steel so shaped, constructed and assembled as to provide a tubularportion in the blade projecting from the outline of the blade at one endto define a handle-receiving ferrule or socket and located in partwithin the overall outline of the blade to form a rigidifying portionstrengthening the blade and accommodating transfer of the load from theblade to the handle ferrule progressively along at least a part of thelength of said blade.

A further object is to provide a shovel blade formed of sheet steel orplate stock of uniform thickness whose thickness is less than thatusually required in such material to withstand the stresses acting upona shovel blade in use, wherein the blade is bent to a shape curved in inevery direction to impart rigidity thereto, and wherein the blade isprovided with a substantially tubular longitudinal part extending for aportion only of its length and merging with a handle-receiving ferruleat its rear end and being of a cross-sectional dimension reducingprogressively from the rear margin of the blade to a point intermediatethe length of the blade.

A further object is to provide a shovel blade which is stamped fromsheet steel and characterized by a substantially continuous transversecurvature and by downwardly and forwardly return bent flanges at'therear transverse margin of the blade interrupted by a centrallongitudinal rearwardly projecting handle-receiving fer- Patented June12, 196

rule and cooperating with said ferrule to rigidify said blade in bothlongitudinal and transverse directions.

'A further object is to provide a shovel blade stamped from sheet steelwhich is characterized by an upwardly offset longitudinal rib at itsrear central portion merging with an integral handle-receiving ferrulewhich is bent adjacent said blade, wherein said blade is reinforced atsaid rib by a member disposed in face engagement with said blade at themargins of the rib-forming offset and positioned completely at or abovethe lowermost level of said blade throughout, said reinforcing memberincluding a tubular portion projecting into and fitting snugly in thebent portion of said ferrule to increase the thickness of said ferruleat the bent portion thereof.

Other objects will be apparent from the following specification. i

In the drawing:

Fig. 1 is a plan view of a shovel blade constituting one embodirnentofmy invention and illustrating in dotted lines the outline of a shovelblade of'diflerent shape utilizing my invention.

Fig. 2 is a side view of the shovel blade with parts shown in section.

Fig.3 is a front edge viewof the shovel blade as viewed in the directionof arrow A in Fig. 2.

Fig. 4 is a transverse sectional view taken on line 4-4' of Fig. 2.

' Fig. 5 is a transverse sectional view taken on line 55 of Fig. 2.

Fig. 6 is a fragmentary transverse sectional view taken on line 66 ofFig. 2. i

Fig. 7 is a fragmentary transverse sectional view taken on line 7--7 ofFig. 2.

,1 Fig. 8 is a fragmentary detail sectional view taken on line 88 ofFig. 1.

Referring to the drawing which illustrates the preferred embodiment-ofthe invention, the numeral 10 designates a shovel blade. This shovelblade may be either of the round nose type shown in full lines in Fig.1, or may be of the squarepoint type shown in'dotted lines in Fig. 1.The blade 10 has a ferrule 12 projecting from the center of its rearedge and adapted to receive a handle (not shown) in the manner wellunderstood in the art.

The blade 10 and ferrule 12 are formed integrally and are formed fromsheet steel. I prefer to form the blade from hot rolled steel, 40-60carbon, of 14 gauge having a thickness in the range between .071 inch to.082 inch. It will be understood, however, that the shovel blades may beformed from other materials and that the material as described above isillustrative and its definition is not intended to be limiting eitherwith respect to its carbon content or its gauge. Any sheet steel ofrequisite strength, capable of forming by stamping or pressing by theuse of dies, may be employed.

The blade is configured or bent along all dimensions thereof, that is,it is bent both longitudinally and transverselyr The transverseconfiguration of the blade at its tip or front edge is illustrated inFig. 3 at 14 as being curved. The curvature preferably is arcuate oruniform, but a true arcuate curvature is not essential.

I At the rear portion of the blade, commencing at a point 16approximately mid-length of the blade 10, the transverse curvature ofthe blade is altered to a compound curvature by the formation therein ofan upwardly olfset longitudinal ridge portion 18. This ridge portion isnarrow at its front end, being substantially pointed at 16 and being ofprogressively increasing lateral and vertical dimension from point 16rearwardly. Thus it will be observed by comparison of Figs. 6 and 7that-both the lateral and the vertical dimensions of the longitudinalcentral rib 18 increase substantially between section lines 7 and 6,respectively. At the part 16 of' the shovel which defines the front ofthe rib 18, the construction provides a somewhat abrupt but neverthelessrounded forward portion of the offset or rib so as to reduce to aminimum the interference of said rib with the operation of insert ingthe shovel blade edgewise into the soil or other compact material inwhich it may be used. It will likewise be observed that the progressiveincrease of both the lateral dimension and the vertical dimension of therib from front to rear affords a wedging action facilitating insertionof the shovel blade into the soil.

The blade M is substantially straight on all longittu dinal lines at itsfront portion, but is bent upwardly at 20 at its rear portion. The bendat 20 is preferably substantially arcuate but not necessarily trulyarcuate. The rearmost edge of the blank at the portion thereofprojecting laterally from the ferrule 12 is downwardly return bent abouta comparatively short radius at 22 to provide a reinforcing flange 24.The bend 22 has a radius greater than the thickness of the sheetmaterial and preferably extends for more than 180 degrees so that thefree front edge of each flange extends into engagement with the adjacentpart of the shovel blade.

The manner in which the front edge of the flange 24 contacts the bottomsurface of the portion 20 of the shovel blade forwardly of the bend 22is illustrated clearly in Figs. 2 and 8. The two flanges 24 extend fromthe outer side edges of the blade for approximately onethird of thewidth of the blade, as well illustrated in Figs. 1 and 3. 1t will beunderstood that this proportion is approximate and illustrative and isnot intended to be limiting. Also, it Will be understood that the lengthof each flange will be determined in part by the lateral width of theoffset or rib 18 at its rearmost portion. As illustrated, the inneredges of the flanges 24 terminate approximately at the point at whichthe general transverse curvature of the blade increases abruptly tostart the definition of the rib 13 rather than being defined by thewidth of the crown portion only of said rib 18.

The ferrule 12 is formed integrally with the blade as an extension ofthe longitudinal rib offset 18 thereof. The ferrule includes a curvedupwardly projecting gooseneck portion 30 and a rear straight upwardlyinclined socket portion 32. As best seen in Fig. 2, the parts are soarranged that the axis 34 of the socket portion 32 is inclined to theblade portion 10 and intersects that blade portion slightly rearwardlyof the front tip 16 of the offset rib 18. Likewise, it will be seen thata part of the axis line 34 passes forwardly of the gooseneck or bentportion 30 so that a substantial part of the axis line 34 is entirelyoutside of the confines of the ferrule 12 and the rib 18. The ferrulepreferably tapers longitudinally with its large dimension being locatedat its open end. The free edges of the sheet metal at 38 at the portionswhich merge between the blank and the ferrule are illustrated in dottedlines in Fig. 8, it being observed in Fig. 2 that said edges are spacedthroughout the major portion of the bent part 30 of the ferrule and arein contact throughout the major portion of the straight part 34 of theferrule.

The shovel is provided with a sheet metal reinforcement member 40. Thisreinforcement member is preferably formed of metal of the same characterand the same gauge as that which forms the blade and the ferrule,although the use of similar or identical material is not essential andthe reinforcement member may be formed of other plate steel stock ofeither lighter or heavier gauge than the blade itself. The inner endportion of the reinforcement member is of generally triangular shape ora shape simulating an arrowhead as is outlined by dotted lines 42 inFig. 1.

The reinforcement member is characterized by a lon gitudinally extendingcentral bend 44 and a pair of laterally spaced similarly reverse bends46, as best illustrated in Figs. 6 and 7. A pair of flanges 48 arelocated at the opposite sides of the reinforcement member 40.

The flanges will preferably be slightly curved and are adapted to bearin face engagement with the bottom surface of the blade 10 insymmetrically spaced relation at opposite sides of the central rib 18 ofthe blade. This rib 18 cooperates with the central longitudinal bend 44of the reinforcement member to define a substantially tubular portionwhich extends full length of the rib 18, being of tapered character soas to increase in dimension from the front end 16 of said rib in arearwardly direction. The reinforcement member 40 is welded at to theblade. The arrangement is preferably such that substantially all partsof the reinforcement member 40 will lie at or above the level of thelowermost portions of the blade 10. Thus, as seen in Figs. 6 and 7, itwill be apparent that no part of the reinforcement member 40 depends orprojects downwardly to any substantial extent below the bottom surfaceof the shovel blade 10. The weld 50 is continuous along both sides andat the front of the rib 18.

The manner in which the central portion 44 of the reinforcement forms asubstantial continuation of the front part of the blade 10 is wellillustrated in Fig. 2. Observe in this connection that there may be avery slight inclination of the part 44 relative to the plane of theblade 10, but where this occurs it occurs to conform to the similarangle of the rear part of the blade 10 compared to its front part due tothe drawing of the metal to form the rib 18.

The longitudinal shape of the reinforcement member 40 is curved toconform to the curvature of the rear bend 20 of the blade 10, as bestseen in Fig. 2. This affords a substantially continuous weldedreinforcmeent of the central portion of the blade 10 from the front part16 of the rib 18 of the blade to the rear edge or bend 22 of the blade.The reinforcement continues upwardly past the rear edge of the bladeentering the ferrule 12 at the bent portion 30 thereof and is formed ina tube 52 at its end. The tube 52 includes a curved neck portion 54 anda rear straight portion. This tube fits snugly within and is insubstantially continuous surface contact with the inner walls of theferrule 12. The snug fit of the tube portions 52 and 54 within theferrule parts 32 and 30,

respectively, is illustrated in Figs. 4 and 5, respectively. In thisconnection observe in Fig. 5 the gap at 56 occurring by reason of thelocation at which the section line is taken slightly beyond the forwardend of the complete tubular formation of the reinforcement part 54. Itwill also be observed at this same point that the gap 58 in the outerferrule 30 occurs as a result of the fact that its edges 38 do notcontact at the point at which the section is taken. It will be observed,however, that the two gaps or interruptions of the ferrule occur atdiametrically opposite parts of the tubular formation so that the tubeitself is continuous even though it is not of double Wall thicknessthroughout. The formation of a continu ous walled tube, with'strengthwhich is inherent and characteristic in a tube, at the bent portion 30of the ferrule is of great importance as a compensation for the lightgauge uniform sheet steel of which the shovel is formed. It will beobserved that the ferrule reinforcing tube extends for only a part ofthe length of the ferrule 32 so that it may define a stop to limit theextent of the insertion of the handle Within said ferrule.

A shovel constructed as described herein is characterized by lightweight and a strength adequate for its intended usage. The reinforcement40 is located at points of greatest weakness of a shovel, namely, at thegooseneck or bent portion of the ferrule and the portion at which theferrule and the shovel blade join. The reinforcement extends for asubstantial part of the length of the blade so that the marginal weldingthereof to the blade tends to distribute, for a substantial part of thelength of the shovel, the stresses which are imparted to the reinforcingmember by or through the ferrule. The continuouscross-sectional tubularshape of the ferrule and of the rear central portion of the bladeimparts to the structure a strength comparable to that of a tubularmember, thus resisting effectively any tendency of the shovel to bend ina direction transverse of the center line of said tubular part. Thiscenter line curves to conform to the upward curvature of the rear edgeof the blade at 20, thence continues upwardly and rearwardly until itmerges with the inclined center line of the ferrule shown at 34. Theextension of the reinforcement member 40 and of the blade 16 to a pointat least as far forward as the point of intersection of the center line34 with the blade also assists in producing requisite strength of thestructure. It will also be noticed that these reinforcement factors aresupplemented by the strength imparted to the structure by the manner inwhich the blade is bent both transversely and longitudinally.

While the preferred embodiment of the invention has been illustrated anddescribed, it will be understood that changes in the construction may bemade within the scope of the appended claims without departing from thespirit of the invention; one such change being an inversion of thelocation of the reinforcing member to the top surface of the shovel withthe ferrule being formed as a continuation of a longitudinal upwardlyconcave portion of the blade located comparably to the concave portion40 of the reinforcement as shown herein.

I claim:

1. In a shovel, a blade and ferrule formed integrally from sheet metal,said blade being bent to define an upwardly offset longitudinal ribextending for a portion of its length and merging with said ferrule,said ferrule being substantially straight and joined to said blade by abent portion so shaped that the axis of said ferrule intersects saidblade adjacent to the front of said rib, and a reinforcing membermarginally secured to the surface of said blade around said rib andinterfitting and cooperating with said bent portion and ferrule todefine a continuous tubular portion from the open end of said ferrule tothe front end of said rib, said tubular portion being of multiplethickness for at least part of its cross-sectional extent throughout thelength of said bent portion and a part of said straight ferrule portion.

2. The construction defined in claim 1, wherein said reinforcing memberis located at and above the level of the adjacent portions of the bottomsurface of said blade.

3. The construction defined in claim 1, wherein said reinforcing memberincludes a tubular end portion having a snug contacting fit in saidferrule for a portion of the length of said straight ferrule portion.

4. The construction defined in claim 1, wherein said reinforcing memberis reverscly bent crosswise thereof to define marginal flanges bearingin face engagement against the bottom surface of said blade at themargins of said rib and also to define a concave surface confronting theconcave bottom surface of said rib.

References Cited in the file of this patent UNITED STATES PATENTS400,923 Little Apr. 9, 1889 657,422 Judd Sept. 4, 1900 1,807,883 WebsterJune 2, 1931 2,031,556 Brandenburg Feb. 18, 1936

